Recent studies have highlighted the significance of co-morbid STIs among HIV+ individuals but few have described their impact in chronic long-term sequelae, particularly among drug users, where primary prevention efforts might be delayed and screening practices might be nonexistent. Human papillomavirus (HPV), one of the most commonly diagnosed STIs world-wide, is of particular concern among persons living with HIV, due to the virus's oncogenic potential and the synergy of HPV infection and neoplasias with HIV coinfections. In men, not only is HPV infection associated with oral, penile and anal cancer, this risk is higher in HIV+ individuals as compared to the general population. Despite reductions in well known risk factors for oral cancers such as tobacco consumption, an augmented incidence of HPV-associated oropharyngeal cancers has been observed in the United States (US) and Puerto Rico (PR) and has been identified as an emerging viral epidemic of cancer. Using data from Dr. Coln-Lopez's NIDA funded study; this study will analyze oral biological specimens and conduct statistical analysis to describe the epidemiological profile of oral HPV infection among male drug users. Specific aims of this study are to: (1) describe the prevalence of oral HPV infection and HPV DNA genotype distribution in an existing sample collected among a clinic-based sample of HIV+/HIV- men 16-65 years in PR; (2) identify factors associated with increased odds of oral HPV infection, including age, HIV status and mode of drug use (IDU/non-IDU) administration; and (3) describe the relationship between prevalent oral and anogenital HPV infection. This application addresses the objectives of the AIDS-Science Track Award for Research Transition (A-START) by 1) supporting a new researcher; 2) serve as a foundation for expanding research to study the intersection of drug abuse, HIV/AIDS and related comorbidities. In addition, the proposed study will characterize the epidemiology of vaccine-preventable diseases and will move research scientists into discussion and development of epidemiological and clinical studies. Also, this opportunity will provide data necessary for future R01-level studies which will further evaluate the potential impact of the HPV vaccine in a reduction of oral HPV infection and subsequent HPV-related cancer risk reduction among men who are HIV+ and also men at high- risk for HIV infection.